1. Field of the Invention
The invention relates to a block management method for a flash memory, and a flash memory controller and a flash memory storage device using the same.
2. Description of Related Art
With the development of the Universal Series Bus (USB) specification and the widespread popularity of flash memory, a portable flash drive has become one of the most popular digital products. Due to the small storage capacity of a floppy disk and the inconvenience of updating data stored in an optical disc, the floppy disk and the optical disc have declined due to the emergence of the flash drive.
For a computer system that has a transmission interface compatible with the flash drive, it is very convenient to write data into the flash drive or read data from the flash drive, not to mention the drastic improvement in data portability. Thus, more and more users utilize flash drives to store various kinds of data, such that data can be processed in a private computer system or a public computer system.
However, a user may lose his flash drive unknowingly due to the compact size of the flash drive. In particular, the internal structure of the flash drive does not include any identification information. Therefore, even though someone may pick up a lost flash drive, it is difficult to give the lost flash drive back to the owner. Moreover, many people may own flash drives which have the same appearance due to the widespread popularity of flash drives. Thus, it may be difficult to identify the owner of a flash drive. In this situation, important data stored in flash drives may be leaked by people who mistakenly recovered the lost flash drives.
Accordingly, in order to avoid important data stored in flash drives from being leaked, setting an authentication code such as a password is desirable. The user can gain an access right to the flash drive by entering a correct authentication information, such as a correct password, into the flash drive. In order to gain access to the flash drive when the flash drive is connected to a computer system, a program is necessary in the computer system for the user to enter the authentication information.
Therefore, in order to prevent the computer system from failing to access the flash drive due to an absence of the authentication program, the program must be stored in the flash drive in advance. However, if the user does not intend to set the authentication code but the flash drive still displays a slot corresponding to the program, the user may feel that the authentication program is inconvenient and unnecessary.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms is a part of the common general knowledge in the art.